Extremely preterm birth is associated with several morbidities ranging from the very severe to the relatively mild, and the risk increases as gestational age decreases.(67) The morbidities include cerebral palsy, mental retardation, learning and language disability, disorders of attention and behavior, visual and hearing impairment, chronic lung disease, gastrointestinal dysfunction, and poor growth.(68–74) Furthermore, survivors may require prolonged hospital stays, in-home nursing and technological services, and societal and state support, all of which add to emotional and financial family burdens.(75, 76) Although there is some relationship between disorders of higher brain function and psychosocial, socioeconomic, and environmental factors,(77, 78) there is now substantial evidence that neurodevelopmental disability arises from poor brain development apart from frank parenchymal brain injury. Former EPTIs have been reported to show decreased regional brain volumes, compared to term controls, including reduced volumes of cortical gray matter, the hippocampi, and corpus callosum, in addition to an increase in the size of the lateral ventricles,(79–87) all of which have adverse neurodevelopmental correlates.

Many articles have documented the short- and long-term outcome of EPTIs. However, as with reports on survival, there can be variability in the results both within and between countries. The causes include variable perinatal and neonatal practices; case ascertainment and attrition rates; gestational age limits and birth weight restrictions; age at follow-up; diagnoses sought; criteria for disability with differing definitions and inclusions; and the use of different methodologies when assessing outcome, including a failure to use concurrent norms.